Kristin Cavallari thanks daughter for giving her strength after brother's death

/ Source: TODAY

It's been less than a week since the tragic death of her brother Michael, and Kristin Cavallari is grateful for the support of her family — especially her newborn daughter, Saylor.

The 28-year-old mom posted a sweet tribute to her baby girl on Instagram Monday, praising the 3-week-old for helping her cope with the devastating news.

"My little angel, Saylor. She has been my light throughout this whole thing and has given me so much strength. Thank you baby girl for coming when u did," Cavallari wrote alongside a photo of Saylor's tiny feet.

Cavallari and husband Jay Cutler welcomed Saylor, their third child, on Nov. 23. The couple, who were married in 2013, also have two sons together: Camden, 3, and Jaxon, 1.

Last Thursday, the former reality star posted a heart-wrenching message about Michael, who was found dead at age 30 after a two-week search.

RELATED: Kristin Cavallari's brother Michael, 30, found dead after 2-week search

"My heart is in a million pieces. Mikey, I could always count on you to make me laugh. You had such a good heart and will be forever missed," she wrote. "I'm at a loss for words but I know u are in a better place and finally at peace. I love u so much RIP."